Firing mechanisms for double barrel,single trigger firearms



Jan. 14, 1969 v. A. BROWNING FIRING MECHANISMS FOR DOUBLE BARREL, SINGLE TRIGGER FIREARMS Sheet Filed Sept. 18, 1967 F/GJ-B INVENTOR VAL A. BROWNING HIS ATTORNEY Jim 4. 1969 v. A. BROWNING 3,42

FIRING MECHANISMS FOR DOUBLE BARREL, SINGLE TRIGGER FIREARMS Filed Sept. 18. 1967 Sheet 3 of 2 F/GJO F/CiQ IN VENTOR. VA'E' A. BROWNING HIS ATTORNEY United States Patent 9 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to double-barrel firearms having single triggers, and provides an improved firing mechanism therefor. In particular, structure is provided so that doubling is avoided during both the recoil and counter-recoil cycles; this is accomplished through use of a connector and counterweight combination which keeps the actuating shoulder (of the counterweight), designed to operate the second sear, away from such sear until all recoil and counter-recoil movement has terminated. Ultimate advancement of the counterweight shoulder to sear engagement is accomplished through release of the first sear, during the fall stroke of the first hammer, to permit the connector and the counterweight to advance forwardly so that the latter ultimately assumes operative position relative to the second sear.

A connector shifting mechanism is provided and, preferably, includes a safety function when the actuating lever is in central position.

The present invention relates to double barrel firearms operated by a single trigger and, more particularly, to a firing mechanism therefor which is constructed to provide a number of advantageous features such as prevention of doubling both during the recoil and counter-recoil cycles of the firearm, provision for misfire so that firing of the second barrel is independent upon the result of the first trigger pull, avoidance of lateral shifts of the connector once the firing order is selected, a safety and firingorder manual control which is easily constructed and operated, and so forth.

Double-barrel firearms, such as shotguns which use but a single trigger to fire both barrels have been manufactured for a number of years. In such a type of firearm there is the ever-present problem of doubling and also of conditioning the firearm for the second shot even though a misfire has occurred instead of the intended first shot. Doubling is known in the industry as unintended double-firing the piece, the second firing occurring involuntarily either during the recoil or counter-recoil cycle of the gun. It is very easy, especially when using a light action trigger, to pull the same quite involuntarily during the initial kick of the first firing or during a time when the gun is rebounding from the shoulder of the user. The term recoil, of course, refers to the firearms rearward movement of kick upon firing of the first shot; counter-recoil refers to the bounce or forward return of the firearm which involuntarily also occurs.

Heretofore, a single connector having oppositely extending lugs has been employed to actuate the sears of the firing mechanism. The problem becomes complicated when the provision of a selector of order-of-firing is incorporated into the firing mechanism. The central basic problem, of course, is to keep the sear-actuating member associated with the connector out of contact with the second sear during the recoil and counter-recoil cycles of the firearm. The inventor accomplishes this in a unique "ice manner by including a counterweight eccentrically pinned to the connector of the mechanism. The enlarged mass of the counterweight is disposed on one side of this pivot, whereas the sear-engaging shoulder or thrust surface of the counterweight is disposed oppositely. During recoil, i.e. the rearward progression of the firearm, the counterweight tends to become rotationally displaced in a clockwise direction against its return spring such that the sear thrusting shoulder thereof is translated rearwardly and out of possible contact with the second sear. The connector and counterweight combination, during the return or counterrecoil of the gun, is displaced rearwardly by virtue of their combined inertia so that the entire combination is maintained away from the second sear. When the gun finally comes to a rest the return spring associated with the connector and the preferably-used spring of the counterweight return these parts to their proper position such that the sear-actuating surface of the counterweight is disposed in line with the sear which it is to actuate and in line with the pivot of the counterweight to the connector. Thus, the upward translation of the connector through depression of the trigger accomplishes actuation of the second sear so as to release the second hammer.

In the embodiment of the invention shown, the connector is provided with a forward portion which is actuated, through the fall of the first hammer, to release the connector from the first sear, thereby enabling the connector-and-counterweight combination ultimately to move forwardly into position with respect to the second sear.

The invention also contains a firing-order selector of unique design, the same incorporating a safety feature for central position; deflection of the lever to the right or left of its normal position achieves first-barrel firing selection, i.e. firing-order selection.

Accordingly, a principal object of the present invention is to provide a new and improved firing mechanism for the firearms of the double-barrel type.

A further object of the invention is to provide in a firing mechanism of the type described a connector element which need be shifted only for the barrel selection and not for second sear actuation during the operating cycle of a particular firing order.

A further object is to provide in the firing mechanism of the type described an improved construction wherein a connector and counterweight combination is provided, the same being constructed in a manner such that actuation of the second sear for releasing the second hammer is prevented until after the recoil and counter recoil cycles of the firearm have been completed upon a first firing of the piece.

Additional object is to incorporate into a single trigger, double-barrel firing mechanism a firing order selector, and associated structure, such that a simpler positioning of the selector automatically accomplishes a safety lock so that the gun cannot be fired, with deflection to the right or to the left of the selector control automatically accomplishing a removal of the safety and the selection of the firing order desired.

An additional object is to provide in a single-trigger, double barrel gun mechanism a connector structure of a type which insures that the second hammer will fall only when the gun completes its back-and-forth movement upon a first firing.

An additional object is to provide in a firing mechanism of the type described a suitable connector means which actuates the second sear, for release of the second hammer, whether the first shot is fired or whether there has been a misfire.

The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by a reference to the following description, taken in connection with the accompanying drawings in which:

FIGURE 1 is a side elevation, partially sectioned and shown in fragmentary view, of a firing mechanism of the single trigger, double barrel firing type; while an overunder structure is shown, the invention will apply equally to side-by-side, double-barrel firearms.

FIGURE 1A is a diagrammatic view of the first hammer, first scar, and connector construction wherein the connector has just lifted the sear from the retentive engagement contact with the hammer, permitting the hammer to commence its fall.

FIGURE 1B is a view of the structure of FIGURE 1A, wherein the hammer, through rapid engagement thereof with the front portion of the connector, has kicked that front portion of the connector rearwardly to permit a disengagement of the connector with the first sear, thereby permitting the first sear to fall.

FIGURE 2 is an elevation similar to that shown in FIGURE 1, but illustrating the first hammer as having fallen to make a first shot, the second hammer remaining for subsequent, second sear release.

FIGURE 3 is a fragmentary top view of the rear portion of the structure shown in FIGURE 1, illustrating the manner in which the firing order selector lever may be positioned, either centrally, to accomplish the safety, or shifted to the left or to the right to accomplish a desired firing order selection.

FIGURE 4 is a perspective view showing further details of the structure illustrated in FIGURE 2.

FIGURES 5 and 6 are side and rear elevations of the trigger employed in the present invention.

FIGURES 7 and 8 are side and rear elevations of the connector used in the present invention; the trigger and connector illustrated in FIGURES 58 and 11 are shown in reduced scale relative to FIGURES 1 and 2.

FIGURES 9 and 10 are a side elevation and rear view of the cylinder (shown in reduced scale), incorporated in the trigger structure to provide an articulative joint of the trigger with the connector.

FIGURE 11 is a sub-assembly, shown in side elevation (and partially sectioned), of the trigger, connector, counterweight, and housing structure associated therewith.

FIGURES 12-14 are side, rear, and top views of a guide block used in conjunction with the rearward extension of the connector in the present invention.

FIGURES 15 and 16 are a bottom view and side elevation of the safety and firing order selector employed.

FIGURES 17-19 are an exploded view of the counterweight structure used in the present invention (the same being shown partially sectioned), and front and rear elevations thereof, respectively.

FIGURES and 21 are a side elevation and top view of the flat spring used in the firearm to advance the connector and trigger forwardly.

FIGURES 22 and 23 are front and side elevations of the lower portion of the tail piece used in the housing construction of the present invention.

In FIGURE 1 the firing mechanism housing 10 is shown to include conventionally configured bore patterns 11 and 12 which receive conventional firing pins 13 and 14. These firing pins are spring-biased by spring means 15 and 16, and the firing pins themselves are provided with slots 17 and 18 for accommodating transverse stop pins 19' and 20'. The configuration and placement of the firing pins as shown in a firearm of this type is strictly conventional and forms no part of the present invention.

Housing 10 includes block portion 19 which is centrally relieved to provide for the pivotal mounting thereto, via pivot pin 20, of hammers 21 and 22. Each of the hammers includes a cocking notch 23 and with which toe 24 of a respective scar 25, 26 cooperates. The sears 25 and 26 are pivoted to the housing by a pivot pin 27, and each of the sears includes a forwardly biasing spring 28, disposed as shown in a compression relationship between the sear and the housing at surface 29. Each of the sears 25, 26 includes a heel 30 which is selectively actuated by a notch 31 including a scar engaging thrust shoulder 32 of connector 33.

At this point it will be desirous to consider the construction of the trigger and connector combination. Trigger 34 is pivoted to the housing 10 by a conventional trigger pivot pin 35. Side and rear elevations of the trigger 34 are illustrated in FIGURES 5 and 6, respectively. The trigger will of course include pivot hole 36 accommodating pin and, also, a relief area 37 having slot indentation 38. Relief area 37 articulatively contains a cylinder 39 having positioning nose 40 fitting into slot 38. The trigger and cylinder are the same width and are retained in position by the trigger housing above G. Cylinder 39 is vertically slotted at 41, as shown in the partially sectioned, side elevation of the cylinder in FIGURE 9. It is this slot 41 which accommodates the pivotal insertion of the lower portion 42 of connector 33. A pivot pin 44 is disposed through aligned apertures 45 to secure the connector 33 to the articulative cylinder 39. FIGURE 10 illustrates a rear elevation of the cylinder shown in FIGURES 9 and 11. In operation, it is the inclusion of cylinder 39 which serves as an articulative, e.g. double pivot axis, joint as between the connector 33 and the trigger 34, see FIGURE 11. Thus the connector may be shifted laterally i.e. from side to side, in order that notch 31 may engage either the left sear 25 or the right sear 26, depending upon the firing order initially selected.

The firing order selector structure and its operation are now to be discussed. The firing order selector 45 in FIG- URE 4 is shown to include a lever 46 having a rearwardly disposed, raised thumb tab 47. Housing 10 includes a transverse aperture 48 serving as a pivoting aperture for pin 49 of the selector 45. A pin 50 is disposed through a corresponding aperture 51 in housing 10 and proceeds through slot 52 of selector pivot pin 49. Pin 50 hence serves as a retainer mechanism for retaining this selector in position upon assembly. The pin 49 has a lower pin extension 53 which serves as a safety stop abutment. In operation this stop abutment is disposed above and proximate to the upper surface 54 of the rearward extension 55 of connector 33. The presence of stop abutment 53 precludes upward movement of the connector 33 upon inadvertent depression of trigger 34, thereby preventing actuation of either sear of the firing mechanism and consequently the inadvertent firing of the piece. The housing is transversely slotted at 56 to provide for the reception of pin 57. Pin 57 receives a block 56 the side, end, and top views of which are illustrated in FIGURES 12, 13, and 14, respectively. Bottom and side views of the firing order selector are illustrated in FIGURES 15 and 16, respectively.

The underside of lever 46 of the firing order selector 45 includes detent depressions 58, 59, and 6%. Depression 59 is a central detent depression whereby the lever is retained in a central position (A) so that the safety at 53 in FIG- URE 11 is operative. The housing includes a spring depression 61 which receives spring 62' backing detent ball 63. The ball cooperates with the depressions 58-60 in physically retaining the lever of the selector in a central position, for safety operation, in a position (B) to the left wherein the left sear and hammer become operative, and in a position to the right, see position C in FIGURE 3, wherein the right sear and hammer are chosen for firstbarrel operation. The operation of the mechanism in this regard is as follows. Slide block 56 includes a central aperture 62 for receiving the depending pin 57 of selector 45. The block 56 also includes an undercut slot 63 disposed on the underside 64 of the block. Specifically, the undercut slot 63 may comprise a conventional slot having an undercut bore area 65 which is easily drilled into the block. Slidably fitting into block 63 will be the tail portion 55 of the connector in 33, see FIGURE 11. Thus, the slot 63 not only accommodates the back-and-forth movement of the connector back-and-forth in a sideways direction in accordance with the positioning of lever 46 in positions A, B, or C, see FIGURE 3. The pivotal mounting of the block upon depending pin 57 in FIGURE 16 permits the block to adjust such that the connector is free to move in its selected longitudinal plane. Hence, there will be a perfect guiding of the connector, with no vertical twisting moment of the connector about a vertical axis being present. Hence, the connector is shifted back and forth in accordance with slight pivotal adjustment about the axis A of cylinder 39. Pivotal adjustment is accomplished through the shifting of the lever 46 and the subsequent lateral shifting of the guide block 56. The positioning of the lever 46 again, is retained by check ball 63.

A very important addition to connector 33 is the inclusion of a counterweight 67. A side elevation (partially sectioned), and front elevation and rear elevations are shown in FIGURES 17, 18, and 19, respectively. A connector 33 includes a pivot aperture 68 which receives pivot pin 69, see FIGURE 2, for pivoting the counterweight 67 to the connector. Counterweight 67 includes an upstanding slot 70, a longitudinal bore 71, and oppositely extending lugs 72 and 73 having respective, upper, sear engaging thrust shoulders 74 and 75. Spring 76 will be disposed in bore 71 and includes a bullet-like cam extension 77 which engages the connector at surface 78 in FIGURE 7. Thus, under the compression action of light compression spring 76 the tip 79 of counterweight 67 will be disposed in engagement with the underside 80 of the connector tail portion or rearward 55.

Before considering the detailed operation of this important structure, there will be summarily considered certain details of the remainder of the structure. FIGURES 20 and 21 are side elevation and plan views of a flat spring 83 as shown in FIGURE 1, employed to urge the connector-and-counterweight combination forwardly. The forward end 84 of spring 83 abuts arcuate portion 85 of the connector. The downwardly turned end 86 of the spring is held in place in slot 87 which is formed by the tailpiece 88 and the rearwardly facing shoulder 89 of slot 87 in housing 10. Tailpiece 88 is shown in fragmentary view and is detailed in FIGURES 22 and 23, these being front and side, fragmentary elevations thereof.

In FIGURES 22 and 23 it is seen that the tailpiece includes counter-bored apertures 95 and 96. These are for the purpose of including spring guide rods 97 and 98. The latter are rearwardly threaded and include, as desired, respective nuts 99. The rods 97 and 98 each include a nose portion 100 which fits into depression 101 of each of the hammers 21 and 22. Each of the rods includes a head 102 which serves as a forward abutment for the forward end of power springs 103 and 104. Springs 103 and 104 respectively serve to power the hamers 21 and 22 forwardly. The rearward ends of the springs of course seat in the respective, counterbored areas of aperture 95 and 96 in FIGURE 1.

It is important to note in connection with the hammer and connector construction that each of the hammers is provided with a slot 105 having a slide shoulder 106. See FIGURE 4 in this regard. Cooperating with and engaging the slide shoulder 106 is a forward extension or nose 107 of connector 33. It is further to be noted in the construction that the pivot of the connector with the trigger is approximately in line with notch 31 of the connector so that depression of the trigger accomplishes an upward raising of the connector and hence an actuation of the sear with which the connector is operatively associated. It will be recalled at this juncture that when the lever 46 of the firing order selector 45 is in central position, pin 53 is in line with the rear portion 55 of the connector so that no possible upward movement of the connector is possible.

There now comes to the very important considerations present in firing the mechanism, to illustrate that inadvertent doubling of the firearm is completely avoided, whereas maintaining the independence of second hammer actuation from the result of first hammer fall is preserved.

Let it be assumed now that the user desires to remove the safety from the firing piece and wishes to select as an order of firing that the left hammer fall with the first depression of the trigger. He will shift the lever 46 of position B. (Position C would have been selected had the user desired the right barrel to fire first.) This accomplishes a lateral movement of the guide block 56 and hence a movement of the left (toward the viewer in FIGURE 1) of connector 33. Again, this movement is enabled through the slight pivotal adjustment of guide block 56 via pin 57 in FIGURE 16, by virtue of the undercut relief area as 65 in FIGURE 13, and further by virtue of the pivotal movement of cylinder 39 in FIGURE 9 and its articulative association with trigger 34. At this point, and referring to FIGURES 1 and 4, it will be seen that the forward extension 107 of connector 33 is completely in line with and engages shoulder 106 of the left hammer. (Engagement with the corresponding shoulder of the right hammer 22 would have been effected for position C selection.) Further, the connector has been translated to the left so that the notch 31 thereof is proximate to and in actuation position with the left sear 25. (Rather than the right sear 26 as would be the case for position C selection.) Depression of trigger 34 raises the connector 33 so as to lift the toe 24 of scar 25 out of notch 23. This enables the hammer 21 to fall forwardly and, in doing so, the shoulder 106 of hammer 21 engages and thrusts upwardly and rearwardly the forward extension 107 of connector 33. See FIGURE 1A. This releases the sear 25, permitting the same, under the pressure of its compression spring 28, to proceed forwardly. Such an action allows the connector 33 ultimately to proceed forwardly, i.e., more forwardly than when the connector was previously associated with sear 33, so that the sear-engagement thrust shoulder 75 of the counterweight may advance to actuation position with respect to the remaining sear 26. Before this is considered, however, We shall consider the condition of the structure immediately upon firing the first hammer and after the condition in FIGURE 1B is achieved.

The first hammer, i.e. hammer 21 falls to strike its associated firing pin at 13. Let us assume that no rnisfire occurs and that the first shell is fired properly. At this point there will occur the conventional kick or recoil of the firearm. As the gun progresses rearwardly the counterweight 67 will lag behind the rearward progression of the gun itself and hence swing in the direction of arrow B, i.e. be rotationally displaced about pivot 69 in a clockwise direction and against the action of compression spring 76 in FIGURE 17. This, in turn, moves the sear thrust shoulder 75 (see FIGURE 19) rearwardly with respect to the right sears position so that during the kick the associated sear engagement thrust shoulder of the counterweight cannot possibly engage the remaining sear 26.

When the piece reaches the rearward extremity of its recoil, the gun will tend to bounce forwardly from the shoulder of the user. This forward momentum of the gun is accompanied by a rearward lagging of the connector and its counterweight, by virtue of the inertia of the latter, so that even though the counterweight returns under the pressure of spring 76 to its initial position relative to the connector, the connector and counterweight combination will nonetheless be disposed rearwardly of the remaining sear. 'I'he fiat spring 83 in FIGUR ES 20-21 and FIGURE 1 lightly urges the connector and counterweight forwardly so that shoulder 75 of the counterweight ultimately comes in actuating position directly underneath the remaining sear 26. See FIGURE 4. At this point the trigger, when pulled, will urge the connector and counterweight upwardly such that the sear thrust engagement shoulder or surface 75 of the counterweight will lift the heel 30 of the remaining sear to accomplish the firing of the second hammer through release of the second sear. Subsequently, the gun is recocked in the usual \manner.

It is to be noted that the conditioning of the second sear for release of the second hammer is independent of the first shot. This is to say, Whether the first sear still advances forwardly, such that the connector can advance forwardly to permit the associated thrust shoulder of its counterweight to come into second-sear actuation position. Thus, release of the first sear is not dependent upon firing the first shot; rather, release of the sear is accomplished immediately through fall of the first hammer, whether such a fall is effective to fire the first shot or not. Where a first shot has occurred, then the recoil of the firearm, again, tilts the counterweight in a clockwise direction about its pivot so that the firing lugs of the counterweight are disposed rearwardly and out of the way of the heel of the remaining sear. Counter-recoil accomplishes a general lagging of the connector and counterweight by virtue of their inertia and mass, relative to the remainder of the structure, so that only after the forward bounce of the firearm has been completed will the counterweight connector advance forwardly under the action of spring 83 to place the related sear thrust shoulder of the counterweight under the heel of the remaining sear.

What is thus accomplished is the provision of a firing mechanism for a double barrel firearm having a number of advantageous features. A safety feature is directly incorporated with a firing order selector so that a single movement to the right or the left of the selector accomplishes both a removal of the safety and a positioning of the connector for first barrel firing. The connector and counterweight combination are effective to keep the second scar from being engaged by the connector-counterweight stmcture until both recoil and counter-recoil have been completed. Additionally, the fall of the first hammer accomplishes a rearward striking of the connector so that the first sear will fall completely forwardly whether a mis-fire occurs on the first shot or not; in any event, and to repeat, the forward progression of the first sear enables the connector and counter-weight structure to advance forwardly, ultimately, such that the firing shoulder of the counterweight comes into engagement with the second sear in the previously described manner.

Finally, it is to be known that there is no need for the connector to be shifted laterally once the firing order has been selected. This is a marked improvement in prior firearms. The connector is shifted only upon movement of the firing order selector lever 46. Once this has been accomplished, the lateral position of the connector remains fixed, i.e. until a next firing order or a safety condition is selected.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects.

I claim:

1. In a single trigger firing mechanism for a doublebarrelled firearm, said firing mechanism including a receiver housing; a pair of side-by-side disposed hammers pivoted within said housing and constructed for longitudinal pivotal movement; spring means cooperating with said hammers and said housing for forwardly spring-biasing said hammers; a pair of forwardly spring-biased sear means pivoted within said housing for releasably retaining said hammers in cocked position, respectively; and trigger means pivoted to said housing and disposed beneath said sear means; an improvement including a connector upstanding from and articulatively connected to said trigger, said connector including a sear-engaging thrust portion for operatively engaging one of said sear means when said hammers are cooked, said connector including a forward portion engaging that one of said hammers to be first released; counterweight means; pin means for eccentrically pivoting said counterweight means to said connector; said one hammer and said connector being so constructed and arranged that the release of said one hammer moves said forward portion sufficiently that said connector becomes disengaged with said first sear means, thereby ultimately permitting said connector with said counterweight means to move forwardly for ultimate engagement by the latter with said second sear means, said counterweight means having a sear thrust shoulder means disposed above said pin means, said connector, counterweight means and hammers being constructed and arranged that, upon the fall of said one hammer, said counterweight sear thrust shoulder is retained from engagement from said sear means associated with the remaining hammer until recoil and counter-recoil cycles of said firearm, when such occur, are completed; and spring means for biasing said connector and said trigger forwardly.

2. Structure according to claim 1 wherein a compression spring is operatively interposed between said counterweight means and said connector.

3. Structure according to claim 1 wherein said connector is laterally shiftable, said housing including manually actuable, firing-order selection means engaging said connector to shift the same laterally.

4. Structure according to claim 3 wherein said firingorder selection means is pivoted to said housing and is slotted and undercut, thereby slideably and articulatively receiving said connector for back-and-forth movement therewithin.

5. Structure according to claim 3 wherein said firingorder selection means also comprises a safety, said housing including stop means constructed and arranged such that when said firing-order selection means is positioned centrally, said stop means limits the upward travel of said connector, thereby preventing hammer release.

6. Structure according to claim 3 wherein said counterweight means includes a pair of sear thrust shoulder means for selectively engaging respective ones of said sears, in accordance with firing-order selection.

7. In a firing mechanism for a double barrel firearm of the single trigger type: a pair of forwardly spring-biased hammers, first and second, forwardly spring-biased sears operatively associated with respective ones of said hammers, for releasably retaining the same in cocked position, a trigger, a connector upstanding from and articulatively connected to said trigger and selectively engaging a respective one of said sears, spring means for forwardly spring-biasing said connector and said trigger, said connector including a forward portion engaging that one of said hammers to be first released, and a counterweight eccentrically connected to said connector and constructed for longitudinal swinging movement within said mechanism, said one hammer and said connector being so con structed and arranged that the release of said one hammer moves said forward portion sufiiciently that said connector becomes disengaged with said first sear, thereby ultimately permitting said connector with said counterweight to move forwardly for ultimate engagement by the latter with said second sear, said counterweight including a sear thrust actuating shoulder operatively disposed underneath the remaining one of said sears after said trigger is first pulled and only when thereafter there is present in the mechanism no recoil or counter-recoil movement in the mechanism.

8. Structure according to claim 7 wherein a compression spring is operatively interposed between said counterweight and said connector.

9. Structure according to claim 7 wherein said counterweight includes a pair of scar thrust actuating shoulders disposed on opposite sides of said connector and operatively disposed beneath the remaining one of said sears, depending upon firing order selection, said trigger is first pulled and only when thereafter there is present in the mechanism no recoil or counter-recoil movement in the mechanism, and means for laterally shifting said connector to thereby predetermine firing order selection by 9 10 positioning the connector in line with that sear and ham- 2,233,861 3/ 1941 Browning 4242 met to be first actuated. 2,711,042 6/ 1955 Simmons 4242 3,142,925 8/ 1964 Miller 4242 References Cited UNITED STATES PATENTS 5 BENJAMIN A. BORCHELT, Primary Examiner. 2,203,378 6/1940 Browning 4242 

